Summary The Robinson R22 helicopter (registration C-FILW), serial number 1457M) was on a flight from a logging camp at Kumealon Inlet to Prince Rupert and return, a distance of approximately 40 nautical miles. There had been a passenger on the leg of the flight to Prince Rupert and the pilot was returning alone. When the helicopter did not arrive at the logging camp, a search was carried out, and a day later the helicopter wreckage was located in the forest near its intended destination at Kumealon Inlet. The helicopter had suffered an in-flight breakup, and one of its two main-rotor blades was missing. The pilot was fatally injured during the in-flight breakup, and his body was found 15 metres away from the cabin/main wreckage. There was no fire. The accident occurred at approximately 1240 Pacific standard time. Ce rapport est galement disponible en franais. Other Factual Information The weather reported from Prince Rupert for that day was suitable for visual flight, with winds at 10to 18knots. The crew of a Boeing107 helicopter reported moderate to severe turbulence and winds blowing at 30to 40knots in the area that day. They had also encountered turbulence in the area of the accident, at the approximate time of the accident, 1240Pacific standard time.1 This turbulence was sufficient to leave the entire contents of the co-pilot's coffee cup in the air and was described as an unusually sharp blow to the Boeing107, which is a heavy and forgiving helicopter in turbulence. The accident helicopter was owned and operated by Bear Creek Contracting Ltd. and was being used by the logging manager, the pilot, to get around the area (like one would use a pick-up truck if terrain and roads permitted). It was registered for private use. The pilot carried out an extensive pre-flight inspection before the first leg of the accident flight. The flight to Prince Rupert was normal and relatively smooth. A few moments before the estimated time of the accident the helicopter was seen flying towards the logging camp, its destination. The Robinson R22 flight manual has flight restrictions if surface winds exceed 25knots, or if the wind gust spread exceeds 15knots. There are also restrictions on continued flight in moderate, severe, or extreme turbulence. These restrictions apply only to pilots with less than 200hours on helicopters, or less than 50flight hours on type, or have not completed the awareness training specified in United States Special Federal Aviation Regulation No.73. The pilot had approximately 1200hours of flying experience on Robinson R22helicopters, had the awareness training specified, and was very familiar with the local environment. The area in the vicinity of the accident site was examined for main-rotor blade strikes to trees. None was found, but the tree branches immediately above the main wreckage impact area were damaged. That damage was not consistent with that found when rotating blades strike a tree. The detached main-rotor blade was found three days after the accident approximately 150metres from the main wreckage site. It was bent more than 90degrees down at approximately 78cm from the blade root. The pitch horn was bent and the pitch change rod was broken. Examination of the wreckage indicated that the blade attachment bolt had broken at the coning hinge, so an extensive search of the area was carried out. Part of the subject bolt was found a week later. It was examined with optical enhancement and determined to have broken/sheared from overload. The other blade attachment bolt was examined and found to demonstrate signatures of an impending shear. Both bolts were tested for hardness and dimension; they met design specifications. The examination also revealed damage to the rotor system droop stops and teeter stops. The teeter stops were of an early design made of aluminium brackets with elastomeric bumpers. The elastomeric bumpers were missing. The droop stops were sheared off in a manner similar to that found when like rotor systems are subjected to negative loading. However, contrary to previous accidents where rotor systems were unloaded, there were no obvious main-rotor strikes to the cabin, landing gear or tail. Robinson Helicopters, the manufacturer of the helicopter, issued a service bulletin (SB-78) in 1995calling for the teeter stops to be changed to a newer design made of stainless steel brackets with elastomeric bumpers. The bulletin was to mitigate the risk of losing the elastomeric bumpers because of failures of the aluminium brackets. While the helicopter manufacturer stated a date of compliance (31July1995) for this airworthiness-related service bulletin, Transport Canada does not require compliance with service bulletins. It is however noteworthy that the service bulletin only referred to problems during starting and stopping the rotors in windy conditions. The main-rotor damage signatures did not indicate excessively low rpm. The engine and its accessories demonstrated signatures of power/rotation at impact. The main-rotor transmission attachment area was torn and deformed. The structural firewall - the aft wall of the cabin - was deformed forward. The plexiglass windshield and roof were broken, and the pieces were found approximately 100metres from the wreckage impact site. The centre post for the windshield was also broken; and part of it, with the compass, was found close to the pilot's body, which was resting along the debris trail before the main wreckage impact site. The main-rotor blade that remained attached to the helicopter had blood stains on the leading edge at 91to 101centimetres from the blade root. The tail-rotor and tail boom damage indicate that the tail-rotor deflected into the tail boom. The sprag clutch assembly was damaged and excessively worn, the wear being uneven, and there were indications of hard engagements and slipping. While the helicopter manufacturer's assigned life for the sprag clutch assembly is 2200hours, the sprag clutch assembly that was installed had 2906.5hours of logged flight time on it. There were several other components that were over their time limits, but there were no indications of excessive wear and tear on them. Light bulb analysis of the caution lights indicate that the main transmission chip (MRCHIP) detector caution light was illuminated at impact. An autopsy of the pilot's body found, among other injuries, an incomplete tear of the pontomedullary junction of the brainstem. The fatal upper body and head injuries suffered by the pilot are consistent with what would be caused by the violent thrashing forces that deformed the helicopter in flight.